Carrier 69NT40-511-199, 69NT40-521 manual Controller Alarms

CODE	TITLE	DESCRIPTION
#
		Inapplicable Functions Display ----------
		This code is only applicable to units without a DataCORDER, that are configured
	Secondary Return	to have four probes. If this is true, it will then display the current secondary return
Cd39	Air Temperature	air temperature.If the unit is configured with a DataCORDER, the Controller
	(Optional)	function code Cd39 will display “----------,” and the display values for RRS will
		appear on the DataCORDER function code dC2.

3.1.5Controller Alarms

The alarm philosophy balances the protection of the refrigeration unit and that of the refrigerated cargo. The action taken when an error is detected always considers the survival of the cargo. Rechecks are made to confirm that an error actually exists.

Some alarms requiring compressor shutdown have time delays before and after to try to keep the compressor on line. An example is a low mains voltage, when the voltage drops over 25%, an indication is given on the display, but the unit will continue to run.

An alarm (See Table 3-4) is indicated by flashing an alarm code on the display panel, and for some alarms, by the alarm light illuminating.

When an Alarm Occurs:

SThe red alarm light will illuminate for “20 series” alarms only.

SIf a detectable problem is found to exist, its alarm code will be alternately displayed with the set point on the left display.

SThe user should scroll through the alarm list to determine what alarms exist or have existed. Alarms must be diagnosed and corrected before the Alarm List can be cleared.

To Display Alarm Codes:

While in Set Point Selection or Default Display mode, press the ALARM LIST key. This accesses the Alarm List Display Mode, which displays any alarms archived in the Alarm Queue. The alarm list stores up to 16 alarms in the sequence in which they occurred. The user may scroll through the list by depressing the UP ARROW key. Depressing the DOWN ARROW key allows the user to scroll backward through the list.

The left display will show “AL#,” where # is the alarm number sequentially in the queue.

The right display will show:

S“AAXX” for an active alarm, where “XX” is the alarm code. See Table 3-4, Controller Alarm Indications.

S“IAXX” for an inactive alarm.

“END” is displayed to indicate the end of the alarm list if any alarms are active. “CLEAr” is displayed if all alarms are inactive.

SThe alarm queue may only be cleared if no alarms are active, other than alarm code AL51, and “CLEAr” is displayed.

To Clear the Alarm List:

If all above conditions have been satisfied, e.g. no alarms are active other than AL51, the alarm queue may be cleared.

SPress the ENTER key. The alarm list will clear and “--------” will be displayed.

NOTE

If the unit is configured for single evaporator fan operation (refer to Table 3-1), and troubleshooting alarms AL11 and AL12, be aware that the presence of 24 vac on the evaporator fan motor internal protector safety sense lines (MC6 and KB10) will indicate a failure condition. This differs from most other circumstances, whereby the absence of 24 vac usually means an alarm condition is present.

T-268-07 3-10